The British Parliament is marking 800 years since the signing of Magna Carta, the document that asserted the principle that the country's ruler is subject to the law, with an exhibition highlighting the expansion of rights down the centuries.

The display in Westminster Hall, the oldest part of the Houses of Parliament in London, opens Tuesday, showing a series of specially commissioned banners marking events such as Parliament's abolition of the slave trade in 1807 and the legalization of homosexuality in 1967. The four surviving original manuscripts of Magna Carta from 1215, which have never been brought together before, will also be displayed in the House of Lords for one day next month.

"Magna Carta established the principle of rule of law and equality before the law," the speaker of the Lords, Frances D'Souza, told reporters in London. "For 800 years we have been influenced by its contents and it remains one of the most important political documents in the world, with countries such as the United States, Australia, New Zealand and Canada tracing constitutional influences back to Magna Carta."

Magna Carta, representing the demands of rebel barons, was authorized by King John on June 15, 1215, at Runnymede, west of London. It dealt with their grievances over his extortionate taxes, arbitrary conduct and denial of justice. As well as encapsulating the rule of law, it also set out that taxation could not be levied with the common assent of the realm, giving the basis for Parliament's future power.

Tuesday also marks the 750th anniversary of the 1265 Parliament summoned by Simon de Montfort, who had defeated King Henry III in battle the previous year and ruled in the king's name. It was the first such gathering that knights and ordinary citizens, not just nobles, were called to attend.